This proposal represents a five-year curriculum and research plan designed to facilitate my development to an independent investigator in patient-oriented aging research. During the five years of the award, I will expand on my health services research training and experience through mentored research, formal coursework, and selfdirected learning activities and develop independence through leadership and networking opportunities. The current pace of U.S. healthcare spending is unsustainable as the oldest segments of the population expand. Hospital services account for the largest portion of Medicare costs, the bulk of which goes to a specific patient population: older adults with serious illness. Geographic regions vary widely in their intensity of hospital use and some argue this represents discretionary or unnecessary hospital-based care. Increased spending is also not associated with higher quality, as measured by longevity, quality of life, and satisfaction. Understanding what factors contribute to unnecessary hospitalizations among at-risk older adults is essential for development of successful new models of efficient, patient-centered care. Thus, the goal of my research is to prospectively identify seriously ill older adults at risk of hih-cost hospital-based care, and identify triggers of potentially avoidable hospitalizations and barriers to remaining in the community for these patients. Specifically, I plan to: (SA1) Build upon my prior work by examining determinants of hospital expenditures, number of hospital admissions and high-intensity, hospital-based treatment in the last year of life among the Health and Retirement Study (HRS) cohort using a mortality follow-back design; (SA2) Expand my earlier findings by evaluating factors associated with hospital expenditures, number of hospitalizations and treatment intensity among a cohort of seriously ill older adults matched prospectively by 1-year mortality risk; and (SA3) Support the development of an intervention to reduce unnecessary hospital admissions among at-risk older adults by investigating reasons for multiple hospital admissions and barriers to management outside the hospital among seriously ill older adults by conducting qualitative interviews with patients, caregivers and primary care physicians. The proposed work uses an innovative combination of regional, patient-level and claims data to evaluate factors driving treatment intensity in this population; examines outcomes with both a traditional mortality follow-back study design and a novel prospective analytic technique; and employs mixed methods to learn from patients and families what problems lead to excess hospitalizations and how those challenges might be overcome. Through my current work and future independent research, I plan to create a patient-centered intervention to reduce unnecessary hospitalizations among seriously ill older adults and translate my work to effective health care policies and clinical programs. The proposed research and career development plan are important initial steps toward advancing the care of older adults by improving medical decision making in the face of serious illness and promoting policies that better align treatments with patient preferences.